RUS  ENG
Full version
JOURNALS // Zapiski Nauchnykh Seminarov POMI // Archive

Zap. Nauchn. Sem. POMI, 1995 Volume 231, Pages 180–190 (Mi znsl3748)

This article is cited in 1 paper

Topology of manifolds and varieties

Estimates of the number of singular points of a complex hypersurface and related questions

O. A. Ivanov, N. Yu. Netsvetaev

Saint-Petersburg State University

Abstract: It is well known that the number of isolated singular points of a hypersurface of degree $d$ in $\mathbb CP^m$ does not exceed the Arnol'd number $A_m(d)$, which is defined in combinatorial terms. In the paper it is proved that if $b^\pm_{m-1}(d)$ are the inertia indices of the intersection form of a nonsingular hypersurface of degree $d$ in $\mathbb CP^m$, then the inequality $A_m(d)<\min\{b^+_{m-1}(d),b^-_{m-1}(d)\}$ holds if and only if $(m-5)(d-2)\ge18$ and $(m,d)\ne(7,12)$. The table of the Arnol'd numbers for $3\le m\le14$, $3\le d\le17$ and for $3\le m\le8$, $d=18,19$ is given. Bibl. 6 titles.

UDC: 515.164

Received: 20.04.1994


 English version:
Journal of Mathematical Sciences (New York), 1998, 91:6, 3448–3455

Bibliographic databases:


© Steklov Math. Inst. of RAS, 2024